In a wireless communications system, distortion may be caused after communication data passes a channel. To resist impact of a radio channel on transmitted data, channel estimation at a receive end is indispensible. In a multicarrier system, a pilot-based channel estimation solution is generally used. A pilot is known data. A transmit end sends a pilot, and a receive end implements, according to received data, channel estimation at a location at which the pilot is sent.
However, the inventor finds in research that in a multicarrier system, especially in a system meeting only a condition of orthogonality in a real number field, a pilot sent by a transmit end may be interfered with by data sent around the pilot. Therefore, data received by a receive end is not a simple product of a channel and the pilot. For example, without considering demodulation noise at the receive end, the received data is specifically a product of the channel and a sum of the pilot and a pilot interference term, and consequently a channel estimation value obtained by means of calculation is inaccurate.